The involvement of protein kinase G inhibitor in regulation of apoptosis and autophagy markers in spatial memory deficit induced by Aβ.

The role of nitric oxide/protein kinase G (NO/PKG) in neurodegenerative disorders is controversial in different circumstances. PKG affects neurons both by itself and as a result of increased NO concentration. In this study, we examined the influence of PKG on spatial memory by intrahippocampal administration of three different concentrations of KT5823 as a PKG inhibitor. Morris water maze (MWM) was used for evaluation of behavioral alterations. We also measured the apoptosis and autophagy markers as two probable interfering pathways with PKG signaling by Western blot method. We found that in Aβ-pretreated rats, intrahippocampus infusions of 2.5, 5, and 10 μm/side of KT5823 led to a significant reduction in escape latency and traveled distance comparing to Aβ-treatment group. Our molecular findings indicated that KT5823 could induce autophagy and attenuate apoptotic markers at distinct doses. Here, we can conclude that in addition to other parameters, apoptosis, and autophagy in part have damaging and protective roles, respectively, in PKG signaling mechanisms. As autophagy-related proteins lose their functions in neurodegenerative diseases, we can suggest that autophagy can be one of the therapeutic aims for remedy of Alzheimer's disease.